1. Field of the Invention
The present invention relates to a camera information coding/decoding method for synthesizing a stereoscopic real video and a computer graphic image, and more particularly, to a camera information coding/decoding method for synthesizing a stereoscopic real video and a computer graphic image, in which camera information required for synthesizing the stereoscopic real video and the computer graphic image is coded upon picturing, and is stored together with contents, thereby shortening a time of calculating the camera information separately and allowing the recorded value to be used.
2. Background of the Related Art
The most general standard among methods of coding digital moving picture contents comprises MPEG-1 format, MPEG-2 format, MPEG-4 format, and MPEG-7 format.
The MPEG-1 format is a standard method of storing data in a storage medium of a constant bit rate, and the MPEG-2 format is a standard for a digital broadcast of high quality, the formats being used in a digital video disc (DVD) and HDTV, respectively.
The MPEG-4 format is a new concept of multimedia coding standard in which an object-oriented idea is firstly introduced. The MPEG-4 format is divided into a scene portion and an object portion. While the conventional standards are divided into an audio portion and a video portion for protecting it, respectively, in view of a simple moving picture, the MPEG-4 format divides the moving picture more closely. Specifically, each of the audio and video is divided by an object, and each object is coded through an optimized method. And then, constructional information of the scene consisting of objects is separately coded, thereby increasing the efficiency.
The MPEG-4 format consists of a visual portion, an audio portion, and a system portion. From now on, it is expected that the multimedia contents coding standards are applied with these concepts, and are continuously developed. In view of these points, the inventors of the present invention proposed a method of storing the camera information as a camera stream object. Moreover, the MPEG-7 format is a searching information coding standard for a search.
The information of the camera happened upon picturing is not contained in the multimedia coding standards, as well as the MPEG formats. Even though the MPEG-7 format has the camera information, it is a method of estimating camera motion through an image processing technique of the video image and storing the estimated resultant. Since the above method contains only information adapted for searching, there is a deficiency in synthesizing the actual image with the computer graphics.
In order to acquire viewpoint information for synthesizing the actual image with the computer graphics, it requires a camera location and a viewpoint upon picturing. Since the existing multimedia coding standards do not contain such information, the environment of the picturing time is reversely estimated to calculate such information and then synthesizing the image. The operation of estimating the camera information is very difficult, so it is hard to acquire the correct resultant.
At present, the contents manufacture of synthesizing the actual image with computer graphics is increased. For example, most of movies employ the computer graphics, and application of virtual information is significantly increased in sportscasts. At that time, a memory header is used to acquire the camera information of the picturing time. On broadcasting a sports game, a score of interested game or information of a player is synthesized with the actual image and is displayed. In addition, since there is no a coding standardizing method of the information of the memory header at present, it is difficult to store the information and apply it. As the image which is recorded, if necessary, is edited and reused, if the pictured image is recorded together with the camera information of the pictured time, it is possible to easily manufacture other contents by synthesizing the actual image with a new computer graphics, if necessary.
Another disadvantage of the existing memory header is that since the information of the camera location displacement can not measured, the location of the camera has to be remained stationary. In case the camera location is displaced, it requires other sensors for measuring the location movement of the camera.